| /* |
| Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de) |
| Copyright (C) 2001 Dirk Mueller (mueller@kde.org) |
| Copyright (C) 2002 Waldo Bastian (bastian@kde.org) |
| Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved. |
| |
| This library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Library General Public |
| License as published by the Free Software Foundation; either |
| version 2 of the License, or (at your option) any later version. |
| |
| This library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Library General Public License for more details. |
| |
| You should have received a copy of the GNU Library General Public License |
| along with this library; see the file COPYING.LIB. If not, write to |
| the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
| Boston, MA 02110-1301, USA. |
| */ |
| |
| #include "config.h" |
| #include "core/fetch/MemoryCache.h" |
| |
| #include "core/dom/CrossThreadTask.h" |
| #include "core/dom/Document.h" |
| #include "core/fetch/ResourcePtr.h" |
| #include "core/frame/FrameView.h" |
| #include "core/workers/WorkerGlobalScope.h" |
| #include "core/workers/WorkerLoaderProxy.h" |
| #include "core/workers/WorkerThread.h" |
| #include "platform/Logging.h" |
| #include "platform/TraceEvent.h" |
| #include "platform/weborigin/SecurityOrigin.h" |
| #include "platform/weborigin/SecurityOriginHash.h" |
| #include "public/platform/Platform.h" |
| #include "wtf/Assertions.h" |
| #include "wtf/CurrentTime.h" |
| #include "wtf/MathExtras.h" |
| #include "wtf/TemporaryChange.h" |
| #include "wtf/text/CString.h" |
| |
| namespace WebCore { |
| |
| static MemoryCache* gMemoryCache; |
| |
| static const unsigned cDefaultCacheCapacity = 8192 * 1024; |
| static const unsigned cDeferredPruneDeadCapacityFactor = 2; |
| static const int cMinDelayBeforeLiveDecodedPrune = 1; // Seconds. |
| static const double cMaxPruneDeferralDelay = 0.5; // Seconds. |
| static const float cTargetPrunePercentage = .95f; // Percentage of capacity toward which we prune, to avoid immediately pruning again. |
| |
| MemoryCache* memoryCache() |
| { |
| ASSERT(WTF::isMainThread()); |
| if (!gMemoryCache) |
| gMemoryCache = new MemoryCache(); |
| return gMemoryCache; |
| } |
| |
| void setMemoryCacheForTesting(MemoryCache* memoryCache) |
| { |
| gMemoryCache = memoryCache; |
| } |
| |
| MemoryCache::MemoryCache() |
| : m_inPruneResources(false) |
| , m_prunePending(false) |
| , m_maxPruneDeferralDelay(cMaxPruneDeferralDelay) |
| , m_capacity(cDefaultCacheCapacity) |
| , m_minDeadCapacity(0) |
| , m_maxDeadCapacity(cDefaultCacheCapacity) |
| , m_maxDeferredPruneDeadCapacity(cDeferredPruneDeadCapacityFactor * cDefaultCacheCapacity) |
| , m_delayBeforeLiveDecodedPrune(cMinDelayBeforeLiveDecodedPrune) |
| , m_liveSize(0) |
| , m_deadSize(0) |
| #ifdef MEMORY_CACHE_STATS |
| , m_statsTimer(this, &MemoryCache::dumpStats) |
| #endif |
| { |
| #ifdef MEMORY_CACHE_STATS |
| const double statsIntervalInSeconds = 15; |
| m_statsTimer.startRepeating(statsIntervalInSeconds, FROM_HERE); |
| #endif |
| m_pruneTimeStamp = m_pruneFrameTimeStamp = FrameView::currentFrameTimeStamp(); |
| } |
| |
| MemoryCache::~MemoryCache() |
| { |
| if (m_prunePending) |
| blink::Platform::current()->currentThread()->removeTaskObserver(this); |
| } |
| |
| KURL MemoryCache::removeFragmentIdentifierIfNeeded(const KURL& originalURL) |
| { |
| if (!originalURL.hasFragmentIdentifier()) |
| return originalURL; |
| // Strip away fragment identifier from HTTP URLs. |
| // Data URLs must be unmodified. For file and custom URLs clients may expect resources |
| // to be unique even when they differ by the fragment identifier only. |
| if (!originalURL.protocolIsInHTTPFamily()) |
| return originalURL; |
| KURL url = originalURL; |
| url.removeFragmentIdentifier(); |
| return url; |
| } |
| |
| void MemoryCache::add(Resource* resource) |
| { |
| ASSERT(WTF::isMainThread()); |
| RELEASE_ASSERT(!m_resources.contains(resource->url())); |
| m_resources.set(resource->url(), MemoryCacheEntry::create(resource)); |
| update(resource, 0, resource->size(), true); |
| |
| WTF_LOG(ResourceLoading, "MemoryCache::add Added '%s', resource %p\n", resource->url().string().latin1().data(), resource); |
| } |
| |
| void MemoryCache::replace(Resource* newResource, Resource* oldResource) |
| { |
| if (MemoryCacheEntry* oldEntry = m_resources.get(oldResource->url())) |
| evict(oldEntry); |
| add(newResource); |
| if (newResource->decodedSize() && newResource->hasClients()) |
| insertInLiveDecodedResourcesList(m_resources.get(newResource->url())); |
| } |
| |
| void MemoryCache::remove(Resource* resource) |
| { |
| // The resource may have already been removed by someone other than our caller, |
| // who needed a fresh copy for a reload. |
| if (!contains(resource)) |
| return; |
| evict(m_resources.get(resource->url())); |
| } |
| |
| bool MemoryCache::contains(const Resource* resource) const |
| { |
| if (resource->url().isNull()) |
| return false; |
| const MemoryCacheEntry* entry = m_resources.get(resource->url()); |
| return entry && entry->m_resource == resource; |
| } |
| |
| Resource* MemoryCache::resourceForURL(const KURL& resourceURL) |
| { |
| ASSERT(WTF::isMainThread()); |
| KURL url = removeFragmentIdentifierIfNeeded(resourceURL); |
| MemoryCacheEntry* entry = m_resources.get(url); |
| if (!entry) |
| return 0; |
| Resource* resource = entry->m_resource.get(); |
| if (resource && !resource->lock()) { |
| ASSERT(!resource->hasClients()); |
| bool didEvict = evict(entry); |
| ASSERT_UNUSED(didEvict, didEvict); |
| return 0; |
| } |
| return resource; |
| } |
| |
| size_t MemoryCache::deadCapacity() const |
| { |
| // Dead resource capacity is whatever space is not occupied by live resources, bounded by an independent minimum and maximum. |
| size_t capacity = m_capacity - std::min(m_liveSize, m_capacity); // Start with available capacity. |
| capacity = std::max(capacity, m_minDeadCapacity); // Make sure it's above the minimum. |
| capacity = std::min(capacity, m_maxDeadCapacity); // Make sure it's below the maximum. |
| return capacity; |
| } |
| |
| size_t MemoryCache::liveCapacity() const |
| { |
| // Live resource capacity is whatever is left over after calculating dead resource capacity. |
| return m_capacity - deadCapacity(); |
| } |
| |
| void MemoryCache::pruneLiveResources() |
| { |
| ASSERT(!m_prunePending); |
| size_t capacity = liveCapacity(); |
| if (!m_liveSize || (capacity && m_liveSize <= capacity)) |
| return; |
| |
| size_t targetSize = static_cast<size_t>(capacity * cTargetPrunePercentage); // Cut by a percentage to avoid immediately pruning again. |
| |
| // Destroy any decoded data in live objects that we can. |
| // Start from the tail, since this is the lowest priority |
| // and least recently accessed of the objects. |
| |
| // The list might not be sorted by the m_lastDecodedFrameTimeStamp. The impact |
| // of this weaker invariant is minor as the below if statement to check the |
| // elapsedTime will evaluate to false as the current time will be a lot |
| // greater than the current->m_lastDecodedFrameTimeStamp. |
| // For more details see: https://bugs.webkit.org/show_bug.cgi?id=30209 |
| |
| // Start pruning from the lowest priority list. |
| for (int priority = MemoryCacheLiveResourcePriorityLow; priority <= MemoryCacheLiveResourcePriorityHigh; ++priority) { |
| MemoryCacheEntry* current = m_liveDecodedResources[priority].m_tail; |
| while (current) { |
| MemoryCacheEntry* previous = current->m_previousInLiveResourcesList; |
| ASSERT(current->m_resource->hasClients()); |
| if (current->m_resource->isLoaded() && current->m_resource->decodedSize()) { |
| // Check to see if the remaining resources are too new to prune. |
| double elapsedTime = m_pruneFrameTimeStamp - current->m_lastDecodedAccessTime; |
| if (elapsedTime < m_delayBeforeLiveDecodedPrune) |
| return; |
| |
| // Destroy our decoded data if possible. This will remove us |
| // from m_liveDecodedResources, and possibly move us to a |
| // different LRU list in m_allResources. |
| current->m_resource->prune(); |
| |
| if (targetSize && m_liveSize <= targetSize) |
| return; |
| } |
| current = previous; |
| } |
| } |
| } |
| |
| void MemoryCache::pruneDeadResources() |
| { |
| size_t capacity = deadCapacity(); |
| if (!m_deadSize || (capacity && m_deadSize <= capacity)) |
| return; |
| |
| size_t targetSize = static_cast<size_t>(capacity * cTargetPrunePercentage); // Cut by a percentage to avoid immediately pruning again. |
| |
| int size = m_allResources.size(); |
| |
| // See if we have any purged resources we can evict. |
| for (int i = 0; i < size; i++) { |
| MemoryCacheEntry* current = m_allResources[i].m_tail; |
| while (current) { |
| MemoryCacheEntry* previous = current->m_previousInAllResourcesList; |
| // Main Resources in the cache are only substitue data that was |
| // precached and should not be evicted. |
| if (current->m_resource->wasPurged() && current->m_resource->canDelete() |
| && current->m_resource->type() != Resource::MainResource) { |
| ASSERT(!current->m_resource->hasClients()); |
| ASSERT(!current->m_resource->isPreloaded()); |
| bool wasEvicted = evict(current); |
| ASSERT_UNUSED(wasEvicted, wasEvicted); |
| } |
| current = previous; |
| } |
| } |
| if (targetSize && m_deadSize <= targetSize) |
| return; |
| |
| bool canShrinkLRULists = true; |
| for (int i = size - 1; i >= 0; i--) { |
| // Remove from the tail, since this is the least frequently accessed of the objects. |
| MemoryCacheEntry* current = m_allResources[i].m_tail; |
| |
| // First flush all the decoded data in this queue. |
| while (current) { |
| // Protect 'previous' so it can't get deleted during destroyDecodedData(). |
| MemoryCacheEntry* previous = current->m_previousInAllResourcesList; |
| ASSERT(!previous || contains(previous->m_resource.get())); |
| if (!current->m_resource->hasClients() && !current->m_resource->isPreloaded() && current->m_resource->isLoaded()) { |
| // Destroy our decoded data. This will remove us from |
| // m_liveDecodedResources, and possibly move us to a different |
| // LRU list in m_allResources. |
| current->m_resource->prune(); |
| |
| if (targetSize && m_deadSize <= targetSize) |
| return; |
| } |
| // Decoded data may reference other resources. Stop iterating if 'previous' somehow got |
| // kicked out of cache during destroyDecodedData(). |
| if (previous && !contains(previous->m_resource.get())) |
| break; |
| current = previous; |
| } |
| |
| // Now evict objects from this queue. |
| current = m_allResources[i].m_tail; |
| while (current) { |
| MemoryCacheEntry* previous = current->m_previousInAllResourcesList; |
| ASSERT(!previous || contains(previous->m_resource.get())); |
| if (!current->m_resource->hasClients() && !current->m_resource->isPreloaded() |
| && !current->m_resource->isCacheValidator() && current->m_resource->canDelete() |
| && current->m_resource->type() != Resource::MainResource) { |
| // Main Resources in the cache are only substitue data that was |
| // precached and should not be evicted. |
| bool wasEvicted = evict(current); |
| ASSERT_UNUSED(wasEvicted, wasEvicted); |
| if (targetSize && m_deadSize <= targetSize) |
| return; |
| } |
| if (previous && !contains(previous->m_resource.get())) |
| break; |
| current = previous; |
| } |
| |
| // Shrink the vector back down so we don't waste time inspecting |
| // empty LRU lists on future prunes. |
| if (m_allResources[i].m_head) |
| canShrinkLRULists = false; |
| else if (canShrinkLRULists) |
| m_allResources.resize(i); |
| } |
| } |
| |
| void MemoryCache::setCapacities(size_t minDeadBytes, size_t maxDeadBytes, size_t totalBytes) |
| { |
| ASSERT(minDeadBytes <= maxDeadBytes); |
| ASSERT(maxDeadBytes <= totalBytes); |
| m_minDeadCapacity = minDeadBytes; |
| m_maxDeadCapacity = maxDeadBytes; |
| m_maxDeferredPruneDeadCapacity = cDeferredPruneDeadCapacityFactor * maxDeadBytes; |
| m_capacity = totalBytes; |
| prune(); |
| } |
| |
| bool MemoryCache::evict(MemoryCacheEntry* entry) |
| { |
| ASSERT(WTF::isMainThread()); |
| |
| Resource* resource = entry->m_resource.get(); |
| bool canDelete = resource->canDelete(); |
| WTF_LOG(ResourceLoading, "Evicting resource %p for '%s' from cache", resource, resource->url().string().latin1().data()); |
| // The resource may have already been removed by someone other than our caller, |
| // who needed a fresh copy for a reload. See <http://bugs.webkit.org/show_bug.cgi?id=12479#c6>. |
| update(resource, resource->size(), 0, false); |
| removeFromLiveDecodedResourcesList(entry); |
| |
| ResourceMap::iterator it = m_resources.find(resource->url()); |
| ASSERT(it != m_resources.end()); |
| OwnPtr<MemoryCacheEntry> entryPtr; |
| entryPtr.swap(it->value); |
| m_resources.remove(it); |
| return canDelete; |
| } |
| |
| MemoryCache::LRUList* MemoryCache::lruListFor(unsigned accessCount, size_t size) |
| { |
| ASSERT(accessCount > 0); |
| unsigned queueIndex = WTF::fastLog2(size / accessCount); |
| if (m_allResources.size() <= queueIndex) |
| m_allResources.grow(queueIndex + 1); |
| return &m_allResources[queueIndex]; |
| } |
| |
| void MemoryCache::removeFromLRUList(MemoryCacheEntry* entry, LRUList* list) |
| { |
| #if ASSERT_ENABLED |
| // Verify that we are in fact in this list. |
| bool found = false; |
| for (MemoryCacheEntry* current = list->m_head; current; current = current->m_nextInAllResourcesList) { |
| if (current == entry) { |
| found = true; |
| break; |
| } |
| } |
| ASSERT(found); |
| #endif |
| |
| MemoryCacheEntry* next = entry->m_nextInAllResourcesList; |
| MemoryCacheEntry* previous = entry->m_previousInAllResourcesList; |
| entry->m_nextInAllResourcesList = 0; |
| entry->m_previousInAllResourcesList = 0; |
| |
| if (next) |
| next->m_previousInAllResourcesList = previous; |
| else |
| list->m_tail = previous; |
| |
| if (previous) |
| previous->m_nextInAllResourcesList = next; |
| else |
| list->m_head = next; |
| } |
| |
| void MemoryCache::insertInLRUList(MemoryCacheEntry* entry, LRUList* list) |
| { |
| ASSERT(!entry->m_nextInAllResourcesList && !entry->m_previousInAllResourcesList); |
| |
| entry->m_nextInAllResourcesList = list->m_head; |
| list->m_head = entry; |
| |
| if (entry->m_nextInAllResourcesList) |
| entry->m_nextInAllResourcesList->m_previousInAllResourcesList = entry; |
| else |
| list->m_tail = entry; |
| |
| #if ASSERT_ENABLED |
| // Verify that we are in now in the list like we should be. |
| bool found = false; |
| for (MemoryCacheEntry* current = list->m_head; current; current = current->m_nextInAllResourcesList) { |
| if (current == entry) { |
| found = true; |
| break; |
| } |
| } |
| ASSERT(found); |
| #endif |
| } |
| |
| void MemoryCache::removeFromLiveDecodedResourcesList(MemoryCacheEntry* entry) |
| { |
| // If we've never been accessed, then we're brand new and not in any list. |
| if (!entry->m_inLiveDecodedResourcesList) |
| return; |
| entry->m_inLiveDecodedResourcesList = false; |
| |
| LRUList* list = &m_liveDecodedResources[entry->m_liveResourcePriority]; |
| |
| #if ASSERT_ENABLED |
| // Verify that we are in fact in this list. |
| bool found = false; |
| for (MemoryCacheEntry* current = list->m_head; current; current = current->m_nextInLiveResourcesList) { |
| if (current == entry) { |
| found = true; |
| break; |
| } |
| } |
| ASSERT(found); |
| #endif |
| |
| MemoryCacheEntry* next = entry->m_nextInLiveResourcesList; |
| MemoryCacheEntry* previous = entry->m_previousInLiveResourcesList; |
| |
| entry->m_nextInLiveResourcesList = 0; |
| entry->m_previousInLiveResourcesList = 0; |
| |
| if (next) |
| next->m_previousInLiveResourcesList = previous; |
| else |
| list->m_tail = previous; |
| |
| if (previous) |
| previous->m_nextInLiveResourcesList = next; |
| else |
| list->m_head = next; |
| } |
| |
| void MemoryCache::insertInLiveDecodedResourcesList(MemoryCacheEntry* entry) |
| { |
| // Make sure we aren't in the list already. |
| ASSERT(!entry->m_nextInLiveResourcesList && !entry->m_previousInLiveResourcesList && !entry->m_inLiveDecodedResourcesList); |
| entry->m_inLiveDecodedResourcesList = true; |
| |
| LRUList* list = &m_liveDecodedResources[entry->m_liveResourcePriority]; |
| entry->m_nextInLiveResourcesList = list->m_head; |
| if (list->m_head) |
| list->m_head->m_previousInLiveResourcesList = entry; |
| list->m_head = entry; |
| |
| if (!entry->m_nextInLiveResourcesList) |
| list->m_tail = entry; |
| |
| #if ASSERT_ENABLED |
| // Verify that we are in now in the list like we should be. |
| bool found = false; |
| for (MemoryCacheEntry* current = list->m_head; current; current = current->m_nextInLiveResourcesList) { |
| if (current == entry) { |
| found = true; |
| break; |
| } |
| } |
| ASSERT(found); |
| #endif |
| } |
| |
| void MemoryCache::makeLive(Resource* resource) |
| { |
| if (!contains(resource)) |
| return; |
| ASSERT(m_deadSize >= resource->size()); |
| m_liveSize += resource->size(); |
| m_deadSize -= resource->size(); |
| } |
| |
| void MemoryCache::makeDead(Resource* resource) |
| { |
| if (!contains(resource)) |
| return; |
| m_liveSize -= resource->size(); |
| m_deadSize += resource->size(); |
| removeFromLiveDecodedResourcesList(m_resources.get(resource->url())); |
| } |
| |
| void MemoryCache::update(Resource* resource, size_t oldSize, size_t newSize, bool wasAccessed) |
| { |
| if (!contains(resource)) |
| return; |
| MemoryCacheEntry* entry = m_resources.get(resource->url()); |
| |
| // The object must now be moved to a different queue, since either its size or its accessCount has been changed, |
| // and both of those are used to determine which LRU queue the resource should be in. |
| if (oldSize) |
| removeFromLRUList(entry, lruListFor(entry->m_accessCount, oldSize)); |
| if (wasAccessed) |
| entry->m_accessCount++; |
| if (newSize) |
| insertInLRUList(entry, lruListFor(entry->m_accessCount, newSize)); |
| |
| ptrdiff_t delta = newSize - oldSize; |
| if (resource->hasClients()) { |
| ASSERT(delta >= 0 || m_liveSize >= static_cast<size_t>(-delta) ); |
| m_liveSize += delta; |
| } else { |
| ASSERT(delta >= 0 || m_deadSize >= static_cast<size_t>(-delta) ); |
| m_deadSize += delta; |
| } |
| } |
| |
| void MemoryCache::updateDecodedResource(Resource* resource, UpdateReason reason, MemoryCacheLiveResourcePriority priority) |
| { |
| if (!contains(resource)) |
| return; |
| MemoryCacheEntry* entry = m_resources.get(resource->url()); |
| |
| removeFromLiveDecodedResourcesList(entry); |
| if (priority != MemoryCacheLiveResourcePriorityUnknown && priority != entry->m_liveResourcePriority) |
| entry->m_liveResourcePriority = priority; |
| if (resource->decodedSize() && resource->hasClients()) |
| insertInLiveDecodedResourcesList(entry); |
| |
| if (reason != UpdateForAccess) |
| return; |
| |
| double timestamp = resource->isImage() ? FrameView::currentFrameTimeStamp() : 0.0; |
| if (!timestamp) |
| timestamp = currentTime(); |
| entry->m_lastDecodedAccessTime = timestamp; |
| } |
| |
| MemoryCacheLiveResourcePriority MemoryCache::priority(Resource* resource) const |
| { |
| if (!contains(resource)) |
| return MemoryCacheLiveResourcePriorityUnknown; |
| MemoryCacheEntry* entry = m_resources.get(resource->url()); |
| return entry->m_liveResourcePriority; |
| } |
| |
| void MemoryCache::removeURLFromCache(ExecutionContext* context, const KURL& url) |
| { |
| if (context->isWorkerGlobalScope()) { |
| WorkerGlobalScope* workerGlobalScope = toWorkerGlobalScope(context); |
| workerGlobalScope->thread()->workerLoaderProxy().postTaskToLoader(createCallbackTask(&removeURLFromCacheInternal, url)); |
| return; |
| } |
| removeURLFromCacheInternal(context, url); |
| } |
| |
| void MemoryCache::removeURLFromCacheInternal(ExecutionContext*, const KURL& url) |
| { |
| if (Resource* resource = memoryCache()->resourceForURL(url)) |
| memoryCache()->remove(resource); |
| } |
| |
| void MemoryCache::TypeStatistic::addResource(Resource* o) |
| { |
| bool purged = o->wasPurged(); |
| bool purgeable = o->isPurgeable() && !purged; |
| size_t pageSize = (o->encodedSize() + o->overheadSize() + 4095) & ~4095; |
| count++; |
| size += purged ? 0 : o->size(); |
| liveSize += o->hasClients() ? o->size() : 0; |
| decodedSize += o->decodedSize(); |
| encodedSize += o->encodedSize(); |
| encodedSizeDuplicatedInDataURLs += o->url().protocolIsData() ? o->encodedSize() : 0; |
| purgeableSize += purgeable ? pageSize : 0; |
| purgedSize += purged ? pageSize : 0; |
| } |
| |
| MemoryCache::Statistics MemoryCache::getStatistics() |
| { |
| Statistics stats; |
| ResourceMap::iterator e = m_resources.end(); |
| for (ResourceMap::iterator i = m_resources.begin(); i != e; ++i) { |
| Resource* resource = i->value->m_resource.get(); |
| switch (resource->type()) { |
| case Resource::Image: |
| stats.images.addResource(resource); |
| break; |
| case Resource::CSSStyleSheet: |
| stats.cssStyleSheets.addResource(resource); |
| break; |
| case Resource::Script: |
| stats.scripts.addResource(resource); |
| break; |
| case Resource::XSLStyleSheet: |
| stats.xslStyleSheets.addResource(resource); |
| break; |
| case Resource::Font: |
| stats.fonts.addResource(resource); |
| break; |
| default: |
| stats.other.addResource(resource); |
| break; |
| } |
| } |
| return stats; |
| } |
| |
| void MemoryCache::evictResources() |
| { |
| for (;;) { |
| ResourceMap::iterator i = m_resources.begin(); |
| if (i == m_resources.end()) |
| break; |
| evict(i->value.get()); |
| } |
| } |
| |
| void MemoryCache::prune(Resource* justReleasedResource) |
| { |
| TRACE_EVENT0("renderer", "MemoryCache::prune()"); |
| |
| if (m_inPruneResources) |
| return; |
| if (m_liveSize + m_deadSize <= m_capacity && m_maxDeadCapacity && m_deadSize <= m_maxDeadCapacity) // Fast path. |
| return; |
| |
| // To avoid burdening the current thread with repetitive pruning jobs, |
| // pruning is postponed until the end of the current task. If it has |
| // been more that m_maxPruneDeferralDelay since the last prune, |
| // then we prune immediately. |
| // If the current thread's run loop is not active, then pruning will happen |
| // immediately only if it has been over m_maxPruneDeferralDelay |
| // since the last prune. |
| double currentTime = WTF::currentTime(); |
| if (m_prunePending) { |
| if (currentTime - m_pruneTimeStamp >= m_maxPruneDeferralDelay) { |
| pruneNow(currentTime); |
| } |
| } else { |
| if (currentTime - m_pruneTimeStamp >= m_maxPruneDeferralDelay) { |
| pruneNow(currentTime); // Delay exceeded, prune now. |
| } else { |
| // Defer. |
| blink::Platform::current()->currentThread()->addTaskObserver(this); |
| m_prunePending = true; |
| } |
| } |
| |
| if (m_prunePending && m_deadSize > m_maxDeferredPruneDeadCapacity && justReleasedResource) { |
| // The following eviction does not respect LRU order, but it can be done |
| // immediately in constant time, as opposed to pruneDeadResources, which |
| // we would rather defer because it is O(N), which would make tear-down of N |
| // objects O(N^2) if we pruned immediately. This immediate eviction is a |
| // safeguard against runaway memory consumption by dead resources |
| // while a prune is pending. |
| // Main Resources in the cache are only substitue data that was |
| // precached and should not be evicted. |
| if (contains(justReleasedResource) && justReleasedResource->type() != Resource::MainResource) |
| evict(m_resources.get(justReleasedResource->url())); |
| |
| // As a last resort, prune immediately |
| if (m_deadSize > m_maxDeferredPruneDeadCapacity) |
| pruneNow(currentTime); |
| } |
| } |
| |
| void MemoryCache::willProcessTask() |
| { |
| } |
| |
| void MemoryCache::didProcessTask() |
| { |
| // Perform deferred pruning |
| ASSERT(m_prunePending); |
| pruneNow(WTF::currentTime()); |
| } |
| |
| void MemoryCache::pruneNow(double currentTime) |
| { |
| if (m_prunePending) { |
| m_prunePending = false; |
| blink::Platform::current()->currentThread()->removeTaskObserver(this); |
| } |
| |
| TemporaryChange<bool> reentrancyProtector(m_inPruneResources, true); |
| pruneDeadResources(); // Prune dead first, in case it was "borrowing" capacity from live. |
| pruneLiveResources(); |
| m_pruneFrameTimeStamp = FrameView::currentFrameTimeStamp(); |
| m_pruneTimeStamp = currentTime; |
| } |
| |
| #ifdef MEMORY_CACHE_STATS |
| |
| void MemoryCache::dumpStats(Timer<MemoryCache>*) |
| { |
| Statistics s = getStatistics(); |
| printf("%-13s %-13s %-13s %-13s %-13s %-13s %-13s\n", "", "Count", "Size", "LiveSize", "DecodedSize", "PurgeableSize", "PurgedSize"); |
| printf("%-13s %-13s %-13s %-13s %-13s %-13s %-13s\n", "-------------", "-------------", "-------------", "-------------", "-------------", "-------------", "-------------"); |
| printf("%-13s %13d %13d %13d %13d %13d %13d\n", "Images", s.images.count, s.images.size, s.images.liveSize, s.images.decodedSize, s.images.purgeableSize, s.images.purgedSize); |
| printf("%-13s %13d %13d %13d %13d %13d %13d\n", "CSS", s.cssStyleSheets.count, s.cssStyleSheets.size, s.cssStyleSheets.liveSize, s.cssStyleSheets.decodedSize, s.cssStyleSheets.purgeableSize, s.cssStyleSheets.purgedSize); |
| printf("%-13s %13d %13d %13d %13d %13d %13d\n", "XSL", s.xslStyleSheets.count, s.xslStyleSheets.size, s.xslStyleSheets.liveSize, s.xslStyleSheets.decodedSize, s.xslStyleSheets.purgeableSize, s.xslStyleSheets.purgedSize); |
| printf("%-13s %13d %13d %13d %13d %13d %13d\n", "JavaScript", s.scripts.count, s.scripts.size, s.scripts.liveSize, s.scripts.decodedSize, s.scripts.purgeableSize, s.scripts.purgedSize); |
| printf("%-13s %13d %13d %13d %13d %13d %13d\n", "Fonts", s.fonts.count, s.fonts.size, s.fonts.liveSize, s.fonts.decodedSize, s.fonts.purgeableSize, s.fonts.purgedSize); |
| printf("%-13s %13d %13d %13d %13d %13d %13d\n", "Other", s.other.count, s.other.size, s.other.liveSize, s.other.decodedSize, s.other.purgeableSize, s.other.purgedSize); |
| printf("%-13s %-13s %-13s %-13s %-13s %-13s %-13s\n\n", "-------------", "-------------", "-------------", "-------------", "-------------", "-------------", "-------------"); |
| |
| printf("Duplication of encoded data from data URLs\n"); |
| printf("%-13s %13d of %13d\n", "Images", s.images.encodedSizeDuplicatedInDataURLs, s.images.encodedSize); |
| printf("%-13s %13d of %13d\n", "CSS", s.cssStyleSheets.encodedSizeDuplicatedInDataURLs, s.cssStyleSheets.encodedSize); |
| printf("%-13s %13d of %13d\n", "XSL", s.xslStyleSheets.encodedSizeDuplicatedInDataURLs, s.xslStyleSheets.encodedSize); |
| printf("%-13s %13d of %13d\n", "JavaScript", s.scripts.encodedSizeDuplicatedInDataURLs, s.scripts.encodedSize); |
| printf("%-13s %13d of %13d\n", "Fonts", s.fonts.encodedSizeDuplicatedInDataURLs, s.fonts.encodedSize); |
| printf("%-13s %13d of %13d\n", "Other", s.other.encodedSizeDuplicatedInDataURLs, s.other.encodedSize); |
| } |
| |
| void MemoryCache::dumpLRULists(bool includeLive) const |
| { |
| printf("LRU-SP lists in eviction order (Kilobytes decoded, Kilobytes encoded, Access count, Referenced, isPurgeable, wasPurged):\n"); |
| |
| int size = m_allResources.size(); |
| for (int i = size - 1; i >= 0; i--) { |
| printf("\n\nList %d: ", i); |
| Resource* current = m_allResources[i].m_tail; |
| while (current) { |
| Resource* prev = current->m_prevInAllResourcesList; |
| if (includeLive || !current->hasClients()) |
| printf("(%.1fK, %.1fK, %uA, %dR, %d, %d); ", current->decodedSize() / 1024.0f, (current->encodedSize() + current->overheadSize()) / 1024.0f, current->accessCount(), current->hasClients(), current->isPurgeable(), current->wasPurged()); |
| |
| current = prev; |
| } |
| } |
| } |
| |
| #endif // MEMORY_CACHE_STATS |
| |
| } // namespace WebCore |
